/*
 * [New BSD License]
 * Copyright (c) 2011-2012, Brackit Project Team <info@brackit.org>  
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the Brackit Project Team nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.brackit.xquery.node.parser;

import org.brackit.xquery.xdm.DocumentException;
import org.brackit.xquery.xdm.Kind;
import org.brackit.xquery.xdm.Node;
import org.brackit.xquery.xdm.Stream;

/**
 * Navigating {@link SubtreeProcessor} for fragments.
 * 
 * @author Sebastian Baechle
 * 
 */
public class NavigationalSubtreeProcessor<E extends Node<E>> extends
		SubtreeProcessor<E> {
	private final E root;

	public NavigationalSubtreeProcessor(E root,
			SubtreeListener<? super E>... listeners) {
		super(listeners);
		this.root = root;
	}

	public void process() throws DocumentException {
		try {
			notifyBegin();
			notifyBeginFragment();
			traverse(root);
			notifyEndFragment();
			notifyEnd();
		} catch (DocumentException e) {
			notifyFail();
			throw e;
		}
	}

	private void traverse(E node) throws DocumentException {
		Kind kind = node.getKind();

		if (kind == Kind.ELEMENT) {
			notifyStartElement(node);

			Stream<? extends E> attributeStream = node.getAttributes();

			try {
				E attribute;
				while ((attribute = attributeStream.next()) != null) {
					notifyAttribute(attribute);
				}
			} finally {
				attributeStream.close();
			}

			Stream<? extends E> childStream = node.getChildren();
			try {
				E child;
				while ((child = childStream.next()) != null) {
					traverse(child);
				}

			} finally {
				childStream.close();
			}

			notifyEndElement(node);
		} else if (kind == Kind.TEXT) {
			notifyText(node);
		} else if (kind == Kind.COMMENT) {
			notifyComment(node);
		} else if (kind == Kind.PROCESSING_INSTRUCTION) {
			notifyProcessingInstruction(node);
		} else if (kind == Kind.ATTRIBUTE) {
			notifyAttribute(node);
		} else if (kind == Kind.DOCUMENT) {
			notifyBeginDocument();
			Stream<? extends E> childStream = node.getChildren();
			try {
				E child;
				while ((child = childStream.next()) != null) {
					traverse(child);
				}
			} finally {
				childStream.close();
			}
			notifyEndDocument();
		} else {
			throw new DocumentException("Illegal node type: %s", kind);
		}
	}
}
